Urinary tract infections represent the most frequent bacterial infectious complications during pregnancy. The gravidic characteristics, especially due to estrogens and progesterone, are responsible for modifications of the urine composition, the physiology and the anatomy of the urinary tract. These modifications increase the risk of bacteriuria, cystitis and acute pyelonephritis. An inadequate treatment or a lack of treatment can have very serious consequences for the women and the foetus. It is important to quickly detect the situations at high risk of complications, to understand when to treat and to use antibiotics known to be harmless for the foetus. An asymptomatic bacteriuria must always be treated with antibiotics according to the results of the antibiogram during five days. Concerning cystitis and acute pyelonephritis, the antibiotic must be first delivered before the result of the antibiogram. After the result of the antibiogram, the antibiotic must be adjusted if it was ineffective for five days for cystitis and for two or three weeks for acute pyelonephritis. The monitoring of the mother and the foetus involve that every acute pyelonephritis during pregnancy must be attended in a specialized unit.
Source